The conventional SIFT algorithm, inter alia disclosed in the U.S. Pat. No. 6,711,293 B1, discloses a method and apparatus for identifying scale invariant features in an image, and the use of these features for locating an object in an image.
The US patent application 2010/0169576 discloses a method for implementing a scale invariant feature transform algorithm, wherein a difference of Gaussian image may be obtained from convolving an input image with a difference of Gaussian filter. While the application purports that the processes may be conducted in parallel, the application is silent about actual parallel implementations.